Disc read retry devices and methods

Abstract

Devices and methods capable of controlling disc read operations are disclosed. For example, an electronic circuit can include an error-severity determining circuit configured to determine a severity of read error that occurs for a block of data read from a disc, and a re-read decision-making circuit that determines whether to re-read the block of data based on the severity of read error.

What is claimed is: 
     
       1. An electronic circuit capable of controlling a read operation from a storage medium, comprising:
 an error-severity determining circuit configured to determine a severity of read error that occurs for a block of data read from the storage medium; 
 a re-read decision-making circuit that determines whether to re-read the block of data based on the severity of read error; and 
 an error correction code circuit configured to determine whether or not the block of data contains an uncorrectable error, and when the error correction code circuit determines that the block of data contains uncorrectable errors, the error-severity determining circuit determines the severity of read error. 
 
     
     
       2. The electronic circuit of  claim 1 , wherein:
 the re-read decision-making circuit determines whether to re-read the block of data based on whether the severity of read error indicates that there will be a correct reading of the block of data upon N number of re-read operations, wherein N is a positive integer. 
 
     
     
       3. The electronic circuit of  claim 2 , wherein N=1. 
     
     
       4. The electronic circuit of  claim 1 , wherein:
 the re-read decision-making circuit determines whether to re-read the block of data based on whether the severity of read error indicates that there will be a correct reading of data with a reduced number or errors upon N number or re-read operations, wherein N is a positive integer. 
 
     
     
       5. The electronic circuit of  claim 4 , wherein N=1. 
     
     
       6. The electronic circuit of  claim 4 , further comprising a defect detector configured to determine a severity of media defect of the storage medium associated with the block of data, and report the type of defect to the error-severity determining circuit. 
     
     
       7. The electronic circuit of  claim 6 , wherein the defect detector is configured to detect a transient servo error associated with the block of data, and report the transient servo error to the error-severity determining circuit. 
     
     
       8. The electronic circuit of  claim 6 , wherein the defect detector is configured to detect lengths and positions of burst errors in the block of data, and report the lengths and positions to the error-severity determining circuit. 
     
     
       9. The electronic circuit of  claim 6 , wherein:
 error-severity determining circuit is configured to determine the severity of a defect associated with the block of data based upon a frequency of zero crossings of the data in the block of data. 
 
     
     
       10. The electronic circuit of  claim 6 , wherein the defect detector is configured to detect defects in compact discs containing audio information. 
     
     
       11. An electronic circuit capable of controlling a disc read operation, comprising:
 an error correction code circuit configured to determine whether or not a block of data read from an optical disc containing digital audio information contains an uncorrectable error; 
 an error-severity determining circuit configured to determine a severity of read error that occurs for the block of data read from a disc when the error correction code circuit determines that the block of data contains uncorrectable errors; and 
 a re-read decision-making circuit that determines whether to re-read the block of data based on the severity of read error, wherein the re-read decision-making circuit determines whether to re-read the block of data based on whether the severity of read error indicates that there will be a reading of the block of data with fewer errors upon N number of re-read operations, wherein N is a positive integer. 
 
     
     
       12. The electronic circuit of  claim 11 , further comprising a defect detector configured to determine lengths and positions of errors with the block of data and a transient servo error associated with the block of data, and report the lengths and positions of errors and/or the servo error to the error-severity determining circuit and the re-read decision-making circuit. 
     
     
       13. The electronic circuit of  claim 11 , wherein:
 the error-severity determining circuit is configured to determine the severity of error associated with the block of data based upon a frequency of zero crossings of the data in the block of data. 
 
     
     
       14. A method for controlling a read operation of a storage medium, comprising:
 determining whether or not a block of data read from the storage medium contains an uncorrectable error; and 
 if the block of data contains an uncorrectable error, determining whether to re-read the block of data based on a severity of uncorrectable error. 
 
     
     
       15. The method of  claim 14 , wherein determining whether to re-read the block of data includes determining whether there will be a reading of the block of data with fewer errors upon N number or re-read operations, wherein N is a positive integer. 
     
     
       16. The method of  claim 15 , wherein N=1. 
     
     
       17. The method of  claim 15 , wherein determining whether to re-read the block of data includes detecting lengths and positions of burst errors in the block of data. 
     
     
       18. The method of  claim 15 , wherein determining whether to re-read the block of data includes determining a frequency of zero crossings of the data in the block of data.